blob: 3a18cfd72943ac9d931c0125575564dcdbeaf6a5 [file] [log] [blame]
// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
library tracer;
import 'dart:async';
import 'package:logging/logging.dart';
_deepCopy(src) {
if (src is Map) {
var dest = {};
src.forEach((key, val) {
dest[key] = _deepCopy(val);
});
return dest;
} else if (src is List) {
var dest = [];
src.forEach((val) {
dest.add(_deepCopy(val));
});
return dest;
} else {
return src;
}
}
class TraceEvent {
TraceEvent.msg(this._time, this.message, Map originalMap) {
map = _deepCopy(originalMap);
}
String get timeStamp => "T+${_time}us";
String toString() {
return "[${timeStamp}] ${message}";
}
int _time;
String message;
Map map;
}
class Tracer {
// The current global tracer.
static Tracer get current => _current;
static Tracer _current;
static void start() {
if (_current == null) {
_current = new Tracer();
}
}
static void stop() {
if (_current != null) {
_current.cancel();
_current = null;
}
}
// The tracer subscribes to all logging events.
StreamSubscription loggerSub = null;
// The start time for the current request.
Stopwatch _time;
// A list of all tracing events for thre current request.
List<TraceEvent> events = <TraceEvent>[];
Tracer() {
_time = new Stopwatch();
_time.start();
loggerSub = Logger.root.onRecord.listen((LogRecord rec) {
// Echo all log messages to the trace.
trace('${rec.level.name}: ${rec.message}');
});
reset();
}
void cancel() {
loggerSub.cancel();
}
void reset() {
_time.reset();
events.clear();
}
TraceEvent trace(String message, {Map map: null}) {
var event = new TraceEvent.msg(_time.elapsedMicroseconds, message, map);
events.add(event);
return event;
}
}